SC-05-02 meeting report, Vienna 2007-05

Report of the meeting of the SC-05-02 Working Group on Audio Connectors
of the SC-05 Subcommittee on Interconnections, held in conjunction with
the AES 122nd Convention in Vienna, Austria, 2007-05-05

The meeting was convened by vice-chair W. Bachmann.

The agenda and the report of the previous meeting, held in San Francisco 2006-10-05, were approved as written.

Open Projects

AES-R3-R: Review of AES-R3-2001: AES standards project report on single programme connector - Compatibility for patch panels of TRS Connectors
To be folded into AES-X113, and retired after AES-X113 is published. There was no progress of AES-X113, therefore no action is required at moment.

AES14-R: Review of AES14-1992 (r2004): AES Standard for professional audio equipment - Application of connectors, part 1, XLR-type polarity and gender
No action requested or required.

AES26-R: Review of AES26-2001 (r2006): AES recommended practice for professional audio - Conservation of the polarity of audio signals
There was an input from Bachmann regarding the redundancy of this standard and referring to the existence of AES14. No other action requested or required.

Development Projects

AES-X105: Modified XLR-3 Connector for Digital Audio
It was agreed that the wording "(under development)" in the Project scope should be deleted because it is not clear to what it is referred to. IEC standard 61076-2-103 about XLR-type connectors was already published in 2004.

There was a discussion about the intent whether the document should be a Report (current intent) or a Standard. Several opinions suggested a standard to be more valuable, but no proposal was made.

Action: Relevant drawings from AES-X119 shall be inserted by Secretary. As the existing text consists of excerpts from AES-X119 the text should be reviewed again in the context of the above mentioned discussion as proposed by J. Brown.

This work should be pushed forward quickly in order to meet the IEC review deadline (middle of 2008) for a possible inclusion of AES-X105 in the IEC standard.

AES-X113: Universal female phone jack
There was a long discussion about this topic and its importance, especially on missing generalized drawings and the bad quality of already included figures. Again the intent was put into question whether a standard would be preferable against just an Information document. The issue was raised that AES cannot publish a standard that just points at one manufacturer's part number - even not in an informative annex.

Action: Generalized drawings are needed to create a specification of the essence. To move on the project Bachmann volunteered to prepare drawings on the arrangement of the female contacts of IEC-pattern and B-gauge capable jacks.

AES-X123: XL Connectors to Improve Electromagnetic Compatibility
J. Woodgate raised the question whether AES-X123 should rather be a project of SC-05-05 instead of SC-05-02. This is because in SC-05-05 there is also an open project dealing with filtering issues and there is possible confusion about parallel work. It was decided that AES-X123 is clearly assigned to SC-05-02 due to specific connector requirements.

The current document actually covers only the shell-to-shell connection. Termination of shields and filtering are not yet included. Discussion on producing one common standard or two separate documents one covering the mechanical and one the electrical filtering issues. It was agreed to produce a complete draft including all the technical specifications and to decide afterwards whether splitting is required or not. There was discussion about how to specify performance characteristics for the filtering. It was agreed not to specify certain implementation details, but to collect information on requirements for the result of the filtering; for example, frequency response.

Action: J. Brown will provide wording for revised rationale and abstract. Drawings should be provided illustrating the application issue. Also conceptual drawings showing a typcial filtering network are needed. Inputs for minimum performance requirements are expected on the basis of typical audio applications.

AES-X130: Data Connector in a XL Connector Shell
New drawings with additional dimensions according to the previous meeting report have been uploaded to the reflector. Also the details in the e-mail announcing the posted files should be considered in this context. All agreed that the minimum number of mating cycles to be incorporated in the draft should be 2500. Bachmann reported that tests have been made with connectors withstanding more than 5000 cycles.

During the discussion on new projects a point was put forward by M. Yonge that the scope needs to be changed to refer specifically to Cat5e.

Action: Drawings with corresponding additions and number of mating cycles to be incorporated in the draft.

AES-X011: Fiber-Optic Audio Connections: Connectors and Cables Being Used and Considered for Audio
Little work has been done on this document until now. It was decided that the secretary should revise the draft according to the report of the San Francisco meeting. There was some discussion on the existing text containing inserted notes and modifications of another editor. A secretariat formatted PWD will be posted soon and the announcing e-mail should indicate specifically the corresponding questions raised in the draft.

Liaisons

Eventually an additional liaison with IEC SC 48B (connectors) could be needed in case of submitting AES-X130 (in addition to AES-X105) to SC 48B.

New projects

The need for smaller rugged connectors has been raised again and discussed without result. D. Rottinghaus brought up an actual project of SC-02-12 ( working group discussing pro-audio applications of IEEE 1394, or "Firewire") where a robust connector for data rates up to 800 Mb/s is needed.

Bachmann asked to introduce a new Cat6 connector in a ruggedized version - which is not compatible with the AES-X130 connector - as a new project. Instead of making an amendment to AES-X130 it is preferred to start a new project. Corresponding Project Initiation form will be produced.

New business

There was no new business.

The next meeting will be scheduled in conjunction with the AES 123rd
Convention in New York, 2007-10.

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